Hello,

I am working with Sentinel-1, -2, -3 and Landsat 8 datasets, trying to combine them. Therefore I need to know which coordinate systems the datasets have and in case there are any differences, perform a reprojection.

I allready know, that Sentinel-1 (S1) and Sentinel-2 (S2) do not use the same projection. All I get from the metadata is, that S2 has a WGS84/UTM projection system and S1 has a geographic reference system, but it is not specified more. Landsat 8 (L8) also uses WGS84/UTM and in the metadata of Sentinel-3 (S3) I find epsg 4326.

Asuming that WGS84 is the datum for all these datasets (S1, S2, S3, L8), I only know the map projection for S2 and L8 (UTM). So I wonder which map projection S1 and S3 are using. Is it an ordinary geographic coordinate system (latitude, longitude)? For S1 data I can choose the map projection within the Range Doppler Terrain Correction in SNAP, so I think here it depends on my selection in SNAP?

Are the projections systems of S1 and S3 fully described with epsg 4326 (=Geographic Lat/Lon?) so I could use gdalwarp to convert S2 and L8 data? Would then all datasets have the same projection and coordinate system?

I might mix up some things, so I am happy for any explanation